问题
选择题
I _______ keep dogs for protection, but now I keep them as pets.
A．would rather
B．had better
C．used to
D．have to
答案
答案：C
词义辨析。would rather宁愿；had better最好；used to 过去常常，现在已不再如此；have to不得不，必须。句意：我过去养狗是为了保护，但是现在我把它们作为宠物养。所以选C。